Hello
I have narrowed a problem with my elektron machinedrum down to the power switch and/or the cables between. The power switch I have located on element14 to replace (arcoelectric H8550VBACA rockerswitch https://au.element14.com/arcolectric/h8550vbaca/switch-dpst-10a-250vac-black-i/dp/273200), but the problem seems to lie with the cables and or the crimp connector. Does anyone know how I can locate these particular crimp connector?
The text on it says AMP D9 | China E96
How did you determine the cable is faulty? I donât see any damage. Cables seldom go bad without a reason (like overheating). Have you tried just unplugging and replugging them?
If it is the cable thereâs probably a loose connector contact. Those connectors look like they are crimped on the wire, you could check for loose contacts in the connector. Have you tried testing them with a multimeter?
Iâm assuming you checked continuity at the switch and theres no power on the âonâ side of the circuit regardless of which direction the switch is flipped. If the switch is actually bad I would also assume you can smell the âburnt componentâ smell when giving it a sniff test. Itâs very unlikely the molex connectors are bad, the wires arenât fusible links so unless they were cut or under some trauma indicated by melting or other physical indication itâs also unlikely they are bad. If you want to verify the switch is bad, remove it and use the switch in an independent circuit with a battery, an appropriate resistor, and an LED light - if the light will not light when you flip the switch, then youâve confirmed the switch is bad. If you confirm the switch is not the problem, at that point youâre looking at components around the switch that limit or would inhibit current, and if itâs not the wires/connectors then youâll need to be really careful because something will probably need to be soldered at that point.
You could similarly (at your own risk, FOR TESTING PURPOSES ONLY) plug the MD into a surge protector in the OFF position, use jumper wires with spade connectors (or jumper wires with alligator clips) to complete the circuit where the switch would go (itâs not a fused switch, it just completes the circuit), then using the power strip as the on/off switch, you could temporarily power it on to verify whether or not the wires really need to be replaced. If you have a multimeter I donât really think this is all necessary but just suggesting options so depending on your situation, you can figure something out.
I think it wouldnât hurt to contact elektronâs support and ask if the parts are available for individual purchase, they no longer service MDâs but from what Iâve seen, the warehouse still stocks some parts.
If any of that seems out of your comfort zone, donât do it, let a person with experience take care of it. This is all pretty straight forward though if youâve already diagnosed it that far.
Good luck, keep that MD alive!
Yes - checked continuity. The positive connection is working, the negative is not. It stops working between the switches final terminal and the internal power supply of the machinedrum.
Currently the unit is powered on again, I just had a jam. but on several ocassions when I was putting it back together, once I realised the problem was with the power supply and cables, it would still not power on again. Thus my conclusion that there is something loose in the cable crimp. It is sporadic. Too much movement, some bend in the cable, not sure.
Hereâs how I narrowed it down.
a) checked continuity between all points from the DC brick supply b) used arduino jumper cables between the two pins and bypassed the switch (which works 100% of the time)
Anywho, yes, contacting elektron is in process, Im just wondering if anyone here can help identify the cables as my post outlines.
Identify what, the gauge of the wire?
The type of connector part - damn I totally did not write that correctly its been a long day of troubleshooting! Iâll edit the opening post, just assumed it was clear with the photos.
Itâs totally understandable so not really an issue but being clear is important to get what you want, and specifically are you talking about the molex (plastic) connector part?
Yes
Maybe someone knows but weâre so far removed from the production of the unit that the part number isnât likely to be very helpful. Hopefully support gets back quickly but if they are laggin my first move would be take some basic measurements then try to visually match the style on digikey or mouser electronics, then Iâd check out the data sheets to see if the measurements match what Iâve noted. I wish I had a specific replacement part in mind if you think thatâs what the problem is, but I would guess itâs more likely that the problem is inside the switch than the molex connectors themselves, unless something is grossly loose or there is some visible electrolysis on one of the metal spades or receiver parts in the clip or on the switch. Is there something that looks like itâs damaged? the pictures look ok but itâs not at a resolution where I can really zoom in and see.
The measurements are a good suggestion for a mouser search. AMP is still around
https://au.mouser.com/manufacturer/te-amp-connectors/featured-products/
However, I just have no categories or terminology for researching these parts. I donât even really know what they are (motherboard crimps? crimp connectors?
As I recall when I had it open it did look like there was a bit of wear on the switch (a bit of brownish tint near the solder of the terminal) so maybe re soldering the cables could also fix it. I might try tomorrow
Before I started soldering Iâd run a few bench tests on using the switch with a basic current limited battery/resitor/ LED circuit and see if you can consistently reproduce the issue just to confirm what the issue actually is. I hate doing it but Iâve taken apart switches of various kinds and repaired the internal tumbling mechanism when it was impossible to replace them, however I donât think this is one of those cases. If youâre talking about the metal crimp ends itâs the female end of a crimp terminal, if the male end is flat itâs usually called a spade, if itâs round it may be referred to as a barrel. I donât think itâs so specific of a thing, you would usually find that type of part used in general electronics or automotive applications, another source of parts might be a car stereo specialist as they often use similar molex and terminals, however Iâm fairly certain mouser or digikey or possibly anyone should have something comparable but the size, of course, will be the key indicator of whether or not it will fit. Also if you intend to replace the wires, the wire gauge should be the same or greater (ie lower numbered gauge = greater size) but it seems like you already know that part.
I canât explicitly tell from your photo but the female end looks like this (approximately)?
I just searched âwired spade connectorâ and got a variety of hits
example: 73F-375-50 3M Electronic Specialty | Mouser
Hereâs something basic about adding and removing pins (or in your case terminals) from molex connectors so you can re-use the connector and replace only the wired/crimp terminal parts.
How to Install and Remove Molex Connectors : 6 Steps - Instructables
Also search youtube for âremove molex connector pinsâ and about a billion hits come up. Should work out ok as long as you make a proper diagnosis, never fear.
sounds like the switch then no?
iâve tried to follow your problem solve but agree with others would be a surprise if itâs the crimps/connectors.
common for the rocker to fail after some time/use.
does it click/feel right when you flip it?
Sorry Im just super confused by your post, I think it is completely missing what I am actually inquiring about and youâve ignored the test Iâve already done to isolate that it is a problem with the cables and the switch (bypassing by using a pair of arduino cables).
I appreciate your effort but do not understand why the automotive cables are being suggested. Do you mean to suggest connecting these to the PCB pin headers? I know from just memory that these automotive spades are too thick to fit, and in this case DANGEROUSLY CLOSE. So completely unsure what you are really suggesting. If it were to attach it to the switch, I would need to unsolder the cables anyways (which you suggest "Before I started soldering ").
Very confusing, whatever you are suggesting sounds like way more complication and effort than reapplying solder with an iron.
Since maybe you arenât understanding what Iâve done to isolate the fact it is a problem with the crimp connectors and/or the switch, here is a photo of how I bypassed them with a new set of cables to actually turn the unit on reliably and consistently.
However, I WANT to be able to use the switch, which is what the meaning of my opening post is all about. So I am asking for what are the type of white plastic connectors used that connect to the pcb. In nowhere in my opening post did I outline I was having trouble troubleshooting it, as I spent an entire day looking over the unit already.
You seem very confident it isnât the plastic crimp connection, but I could easily imagine an assembly failing to cut enough length to the exposed wire before entering it into the sleeve, and thus not making proper contact consistently. Iâm not sure. I have no idea why it is not consistently reading continuity. All I know is that SOMETIMES am not getting any continuity between Negative PIN from the first pin junction to the negative pin of the LAST pin junction. Sometimes it doesnât work - move the cable slightly- suddenly it works- reassemble- suddenly doesnt work again-- disassemble â check continuity â no continuity-- move cable â continuity-- reassemble-- working but mentall worried this could happen before a gig.
Your experience with automotive car stereo electronics seems pretty limited and your frustration is understandable. The pin connections are much smaller than what youâre thinking of. Iâm not suggesting replace the white plastic housing, Iâm saying a variety of pin terminals are available for a variety of applications, automotive or otherwise. You would replace the connections inside the the housing (connector) and re-use the difficult to replace housing.
I feel as though there is certainly a disconnect between what we are trying to convey to each other here. The pin terminals are held in place by small metal tabs which one must go to a great deal of trouble to release from the plastic connectors, they are very firmly in place, if you have located that one is out of place and has backed out of the plastic connecter by way of attempting to remove and reinsert then I will leave it to your judgement to determine if that is the issue.
The connection you are showing here as having bypassed the switch shows continuity using jumpers with 2 wires between the plastic connectors, having taken the switch out of the loop.
At the same time youâre saying that the problem is that you believe the connectors which youâre jumping to be the problem, not the switch in between. Youâre asking for help locating rare parts, Iâm telling you to work with whatâs available instead of assuming youâll be able to get the factory parts, maybe you will and that would be preferable, maybe you wonât and youâll need a backup plan. If you want to desolder the wires and wiggle them around to check for a short while measuring continuity to see if thatâs the issue, at that point you may as well just replace the wires and be done with it. Before soldering or desoldering any piece of equipment I didnât build and might not be able to back out of the repair, I try everything possible to verify what the problem is and it sounds as though you are satisfied with what youâve done to eliminate the switch as the cause of the break.
I am only one individual person on this forum attempting to respond to your questions, using my limited experience repairing broken electronics. Giving you an answer you arenât satisfied with and seeing your frustration is enough for me to know my help is unwanted so Iâll bow out and let you wait for someone with replacement part numbers on hand as it seems thatâs what will satisfy your request. Best of luck with your repairs and welcome to Elektronauts.
They are not the âplastic connectorsâ. Those are the pins of the PCB.
So was it the switch? If it was, what was the part number of the replacement please?
In answer to my own question (having removed the switch and read what is written on the side of it) I have ordered the following replacement:
Arcolectric H8550VBACA Rocker Switch DPST On-Off 250V AC 10 A
